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1.
Curr Biol ; 31(9): 1872-1882.e5, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33848458

RESUMO

Leopards are the only big cats still widely distributed across the continents of Africa and Asia. They occur in a wide range of habitats and are often found in close proximity to humans. But despite their ubiquity, leopard phylogeography and population history have not yet been studied with genomic tools. Here, we present population-genomic data from 26 modern and historical samples encompassing the vast geographical distribution of this species. We find that Asian leopards are broadly monophyletic with respect to African leopards across almost their entire nuclear genomes. This profound genetic pattern persists despite the animals' high potential mobility, and despite evidence of transfer of African alleles into Middle Eastern and Central Asian leopard populations within the last 100,000 years. Our results further suggest that Asian leopards originated from a single out-of-Africa dispersal event 500-600 thousand years ago and are characterized by higher population structuring, stronger isolation by distance, and lower heterozygosity than African leopards. Taxonomic categories do not take into account the variability in depth of divergence among subspecies. The deep divergence between the African subspecies and Asian populations contrasts with the much shallower divergence among putative Asian subspecies. Reconciling genomic variation and taxonomy is likely to be a growing challenge in the genomics era.


Assuntos
Panthera , Animais , Ásia , Gatos , Ecossistema , Genômica , Filogeografia
2.
PLoS One ; 15(6): e0234385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32603327

RESUMO

Utilising a reconstructed ancestral mitochondrial genome of a clade to design hybridisation capture baits can provide the opportunity for recovering mitochondrial sequences from all its descendent and even sister lineages. This approach is useful for taxa with no extant close relatives, as is often the case for rare or extinct species, and is a viable approach for the analysis of historical museum specimens. Asiatic linsangs (genus Prionodon) exemplify this situation, being rare Southeast Asian carnivores for which little molecular data is available. Using ancestral capture we recover partial mitochondrial genome sequences for seven banded linsangs (P. linsang) from historical specimens, representing the first intraspecific genetic dataset for this species. We additionally assemble a high quality mitogenome for the banded linsang using shotgun sequencing for time-calibrated phylogenetic analysis. This reveals a deep divergence between the two Asiatic linsang species (P. linsang, P. pardicolor), with an estimated divergence of ~12 million years (Ma). Although our sample size precludes any robust interpretation of the population structure of the banded linsang, we recover two distinct matrilines with an estimated tMRCA of ~1 Ma. Our results can be used as a basis for further investigation of the Asiatic linsangs, and further demonstrate the utility of ancestral capture for studying divergent taxa without close relatives.


Assuntos
Genoma Mitocondrial , Viverridae/genética , Animais , Sudeste Asiático , DNA Mitocondrial/genética , DNA Mitocondrial/história , Bases de Dados de Ácidos Nucleicos , Evolução Molecular , Extinção Biológica , Fósseis/história , Especiação Genética , História Antiga , Filogenia , Filogeografia , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie , Viverridae/classificação
3.
Herz ; 37(2): 123-7, 2012 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-22382138

RESUMO

In-stent restenosis and stent thrombosis are still the main topics of any update on coronary intervention. One of the challenging issues in the past year lay in answering the question of whether the data on first-generation drug-eluting stents are still relevant in the light of newer stent designs and drugs. Other issues include new strategies in antiplatelet therapy, treatment of in-stent restenosis, particularly drug-eluting stent restenosis, treatment of multivessel and left-main disease, as well as the latest developments in bioresorbable polymers and "scaffolds". In the light of demographic changes, the main challenge for the interventional community is to build an evidence base for the adequate treatment of elderly patients in order to resolve uncertainties in the treatment of this challenging patient group.


Assuntos
Prótese Vascular/efeitos adversos , Prótese Vascular/tendências , Doença da Artéria Coronariana/cirurgia , Reestenose Coronária/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Stents/efeitos adversos , Stents/tendências , Doença da Artéria Coronariana/complicações , Reestenose Coronária/etiologia , Humanos
4.
Z Gerontol Geriatr ; 45(1): 17-22, 2012 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-22278002

RESUMO

Diabetes mellitus is a known risk factor for cognitive dysfunction and dementia. Chronic hyperglycemia, genetic predisposition, arterial hypertension, hyperlipoproteinemia, micro- and macrovascular diseases, and depression play a major role in the development of cognitive dysfunction. Both pathophysiology of diabetes and dementia and the specifics of diabetes therapy in patients with dementia are presented in this review.


Assuntos
Demência/diagnóstico , Demência/terapia , Complicações do Diabetes/diagnóstico , Complicações do Diabetes/terapia , Demência/complicações , Alemanha , Humanos
5.
Eur Radiol ; 22(1): 51-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21845463

RESUMO

OBJECTIVES: Transcatheter Aortic Valve Implantation (TAVI) is an alternative to surgical valve replacement in high risk patients. Angiography of the aortic root, aorta and iliac arteries is required to select suitable candidates, but contrast agents can be harmful due to impaired renal function. We evaluated ECG-triggered high-pitch spiral dual source Computed Tomography (CT) with minimized volume of contrast agent to assess aortic root anatomy and vascular access. METHODS: 42 patients (82 ± 6 years) scheduled for TAVI underwent dual source (DS) CT angiography (CTA) of the aorta using a prospectively ECG-triggered high-pitch spiral mode (pitch = 3.4) with 40 mL iodinated contrast agent. We analyzed aortic root/iliac dimensions, attenuation, contrast to noise ratio (CNR), image noise and radiation exposure. RESULTS: Aortic root/iliac dimensions and distance of coronary ostia from the annulus could be determined in all cases. Mean aortic and iliac artery attenuation was 320 ± 70 HU and 340 ± 77 HU. Aortic/iliac CNR was 21.7 ± 6.8 HU and 14.5 ± 5.4 HU using 100 kV (18.8 ± 4.1 HU and 8.7 ± 2.6 HU using 120 kV). Mean effective dose was 4.5 ± 1.2 mSv. CONCLUSIONS: High-pitch spiral DSCTA can be used to assess the entire aorta and iliac arteries in TAVI candidates with a low volume of contrast agent while preserving diagnostic image quality.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/diagnóstico por imagem , Cateterismo Cardíaco , Meios de Contraste/administração & dosagem , Angiografia Coronária , Implante de Prótese de Valva Cardíaca , Artéria Ilíaca/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Idoso de 80 Anos ou mais , Valva Aórtica/patologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/patologia , Estenose da Valva Aórtica/fisiopatologia , Artefatos , Índice de Massa Corporal , Cateterismo Cardíaco/métodos , Meios de Contraste/efeitos adversos , Angiografia Coronária/métodos , Eletrocardiografia , Feminino , Humanos , Artéria Ilíaca/patologia , Artéria Ilíaca/cirurgia , Masculino , Período Pré-Operatório , Estudos Prospectivos , Doses de Radiação , Reprodutibilidade dos Testes
6.
Herz ; 36(5): 386-95, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21750973

RESUMO

In the 20 years since its introduction, radial access for diagnostic and interventional coronary procedures has been well validated in countless scientific studies. Nevertheless, the use of this access route varies greatly among--and even within--countries. Fear of the unknown may make some experienced interventionalists hesitant to adopt the transradial approach in spite of its proven advantages. In our review, we describe practical aspects of the transradial access, such as the role of Allen's test in patient selection and considerations on the optimal puncture technique of the radial artery. Catheter selection, anatomic variations which may complicate access, as well as strategies to avoid and/or manage possible complications are outlined. Finally, we review the literature on the reduction of access site complications by adopting the transradial approach. Even in interventions for acute myocardial infarction, transradial access can be used safely and effectively. In addition to a reduced rate of access site complications, a reduction in overall in-hospital major adverse cardiac events has been demonstrated. The advantage regarding access site complications could be seen even when closure devices were utilized for transfemoral procedures.


Assuntos
Angioplastia Coronária com Balão/métodos , Cateterismo Cardíaco/métodos , Angiografia Coronária/métodos , Infarto do Miocárdio/diagnóstico , Artéria Radial , Angioplastia Coronária com Balão/instrumentação , Angioplastia Coronária com Balão/estatística & dados numéricos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/estatística & dados numéricos , Angiografia Coronária/instrumentação , Angiografia Coronária/estatística & dados numéricos , Hematoma/etiologia , Hemorragia/etiologia , Humanos , Doença Iatrogênica , Infarto do Miocárdio/terapia , Segurança do Paciente , Seleção de Pacientes , Punções , Ensaios Clínicos Controlados Aleatórios como Assunto , Revisão da Utilização de Recursos de Saúde
7.
Eur J Echocardiogr ; 11(7): 557-76, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20688767

RESUMO

Transoesophageal echocardiography (TOE) is a standard and indispensable technique in clinical practice. The present recommendations represent an update and extension of the recommendations published in 2001 by the Working Group on Echocardiography of the European Society of Cardiology. New developments covered include technical advances such as 3D transoesophageal echo as well as developing applications such as transoesophageal echo in aortic valve repair and in valvular interventions, as well as a full section on perioperative TOE.


Assuntos
Ecocardiografia Tridimensional/métodos , Ecocardiografia Transesofagiana/métodos , Cardiopatias/diagnóstico por imagem , Angioplastia Coronária com Balão/métodos , Valva Aórtica/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias/terapia , Doenças das Valvas Cardíacas/diagnóstico por imagem , Próteses Valvulares Cardíacas , Humanos , Valva Mitral/diagnóstico por imagem , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Ultrassonografia de Intervenção
8.
Eur J Echocardiogr ; 11(7): 584-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20200001

RESUMO

AIMS: Regional myocardial function may change differently in different pathology. Speckle tracking echocardiography (STE) was applied to evaluate longitudinal, radial, and circumferential function in patients with aortic stenosis (AS) before, within 1 week, and 6 months after aortic valve replacement (AVR). METHODS AND RESULTS: In 40 consecutive patients with severe AS, we acquired apical four-, three-, and two-chamber views and standard short-axis view pre- and post-AVR and after 6 months. Longitudinal, radial, and circumferential (LS, RS, and CS) were calculated by commercial STE software. Further, we analysed diastolic myocardial function by measuring E/e' ratio. With AVR, valve area increased and remained stable at 6 months follow-up. Left ventricular mass was unchanged 1 week after AVR (270 +/- 58 g vs. 267 +/- 58 g, n.s.) but decreased significantly during the next 6 months (219 +/- 50 g, P < 0.05). Left ventricular ejection fraction remained unchanged. Strain values did not change significantly within 1 week after AVR but increased significantly after 6 months (LS by 16%, RS by 21%, and CS by 28% of baseline values). E/e' ratio was highly augmented before AVR (26.1 +/- 12.5) and decreased significantly 6 months after AVR (15.9 +/- 5.9). CONCLUSION: Myocardial function significantly recovers after replacing the stenosed aortic valve. However, there is a considerable difference between the response of longitudinal, radial, and circumferential function. Our data suggest that echocardiographic assessment of regional function is feasible and of potential clinical importance.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Ecocardiografia/métodos , Implante de Prótese de Valva Cardíaca , Disfunção Ventricular Esquerda/prevenção & controle , Idoso , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Feminino , Próteses Valvulares Cardíacas , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Recuperação de Função Fisiológica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Resultado do Tratamento
9.
Heart ; 95(13): 1056-60, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19389719

RESUMO

BACKGROUND: Multidetector CT allows detection of coronary artery calcium and, after contrast injection, visualisation of the coronary artery lumen. It is commonly assumed that the absence of coronary calcification makes the presence of obstructive coronary lesions highly unlikely. This study evaluates the clinical characteristics of patients with at least one symptomatic, high-grade coronary artery stenosis in both computed tomography and invasive angiography but absence of any coronary calcification and compares the results with patients with stenoses in the setting of detectable coronary calcium PATIENTS AND METHODS: The study retrospectively identified 21 consecutive patients with symptoms in whom a high-grade coronary artery stenosis had been identified in 64-slice or dual-source CT coronary angiography (Siemens Sensation 64 or Siemens Definition, 120 kV, 50 to 85 ml of intravenous contrast at 5 ml/s) in the absence of coronary calcium and in whom that finding had been confirmed by invasive coronary angiography. Clinical presentation ("unstable": all forms of acute coronary syndrome versus "stable": stable chest pain or dyspnoea on exertion) and standard cardiovascular risk factors were assessed, and the results were compared with 42 consecutive patients with symptoms in whom both coronary calcium and coronary stenoses had been identified in computed tomography and invasive coronary angiography. RESULTS: The majority of patients with coronary stenoses in the absence of coronary calcium presented with "unstable" symptoms (non-ST-segment elevation myocardial infarction (NSTEMI) or unstable angina), significantly more frequently than patients with detectable calcification (71% vs 26%, p = 0.001). The age range of patients without calcium was 33 to 76 years, their mean age was younger (53 (SD 13) vs 63 (8) years, p<0.001), but none of the risk factors showed any significant difference compared with patients with calcification. CONCLUSION: The presence of significant coronary artery stenosis in the absence of coronary calcium is possible. It is more likely in the setting of unstable angina or NSTEMI than in stable chest pain and occurs more frequently in younger patients.


Assuntos
Calcinose/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária/métodos , Estenose Coronária/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X
10.
Rofo ; 181(4): 332-8, 2009 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-19291602

RESUMO

PURPOSE: Spiral CT angiography (CTA) of the coronaries using low-pitch scanning and ECG-gated image reconstruction is a robust method for detecting or excluding relevant coronary plaque. However, the resulting dose exposure is considerable. The aim of the present study was to evaluate image quality and artifacts as well as to record dose values for sequential coronary CTA using a 128-slice scanner with a temporal resolution of 150 ms. MATERIALS AND METHODS: 20 patients with a regular heart rate and without contraindications for oral/I.V. beta blockers, who were referred for CTA of the coronaries for exclusion or detection of relevant plaques, were examined by sequential CTA with the following parameters: 120 kV, 200 ref mAs, collimation 2 x 64 x 0.6, table feed of 34.5 mm at a detector width of 38.4 mm. A total acquisition time of 380 ms per table position allowed for mild shifting of the reconstruction window within the cardiac cycle of +/- 5 %. 50 ml of contrast agent were injected at 5 ml/s followed by a 50 ml split bolus (20 % contrast). The individual start delay was determined by a test bolus scan (10 ml contrast + 50 ml saline flush at 5 ml/s). The image quality for each segment, coronary artery, and patient was determined on a 4-point scale. Dose values were estimated based on the individual dose length product as provided by the scanner's patient protocol. Artifacts were evaluated to determine the cause (calcium vs. motion). RESULTS: All patients received beta blocker pretreatment. The mean heart rate was 62 +/- 5 beats/min. 5 % (13 / 286) of all segments in 5 / 20 patients were rated as non-diagnostic. The mean dose length product was 213 mGy x cm, and the mean effective dose was 3.6 mSv. Calcifications were the major cause of non-diagnostic images. However breathing or other motion artifacts occurred as well. CONCLUSION: In select patients with effective heart rate control and thorough instruction for breath hold compliance, sequential CTA of the coronaries using a 128-slice scanner with a temporal resolution of 150 ms is technically feasible. The resulting effective dose values are clearly below those of spiral coronary CT scans.


Assuntos
Carga Corporal (Radioterapia) , Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Radiometria , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Inflamm Res ; 58(6): 306-11, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19190856

RESUMO

OBJECTIVE AND DESIGN: Atherosclerosis, as an inflammatory disease, is characterized by pathologically altered levels of cytokines. We investigated whether smoking affects the CD40/CD154 system and pro-inflammatory cytokines in young males without other risk factors for atherosclerosis. SUBJECTS: Young male smokers (n=13) and 14 non-smoking controls were investigated. METHODS: The differences in CD40/CD154 system and serum cytokines between the groups were measured using flow cytometry and ELISA. RESULTS: In smokers, there was a strong trend (P<0.06) for increased CD40 expression on platelets as compared with non-smokers. However, there were no significant differences in CD40 expression on monocytes or in CD154 expression on platelets and T-cells between smokers and non-smokers. There was a strong trend for increased platelet-monocyte aggregates in smokers (P<0.06). Also, smokers had slightly but not significantly elevated hsCRP and IL-6 levels, and slightly decreased TNF-alpha and MCP-1. Interestingly, IL-18, a cytokine which has the ability to promote both Th1 and Th2 responses, was significantly decreased in smokers group (P=0.03 vs controls). CONCLUSIONS: In young healthy males, smoking is not associated with dramatic changes in CD40/CD154 system. However, cigarette smoke alters the secreted cytokine profile, leading to significant decrease in systemic IL-18 levels.


Assuntos
Aterosclerose/imunologia , Antígenos CD40/imunologia , Ligante de CD40/imunologia , Citocinas/sangue , Fumaça/efeitos adversos , Adulto , Aterosclerose/sangue , Humanos , Interleucina-18/sangue , Masculino
12.
Eur J Radiol ; 72(1): 85-91, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18619752

RESUMO

OBJECTIVE: Assessment of left ventricular function is possible in contrast-enhanced cardiac CT data sets. However, rapid ventricular motion especially in systole can lead to artifacts. Dual Source Computed Tomography (DSCT) has high temporal resolution which effectively limits motion artifact. We therefore assessed the accuracy of DSCT to detect regional left ventricular wall motion abnormalities in comparison to invasive cine angiocardiography. METHODS: We analyzed DSCT data sets of 50 patients (39 male, 11 female, mean age: 61+/-10 years) which were acquired after intravenous injection of 55-70 mL contrast agent (rotation time: 330 ms, collimation: 2 mm x 64 mm x 0.6 mm, 120 kV, 380 mAs, ECG-correlated tube current modulation). 10 data sets consisting of transaxial slices with a slice thickness of 1.5 mm, an increment of 1.0 mm and a matrix of 256 x 256 pixels were reconstructed at 10 time instants during the cardiac cycle (0-90% in 10% increments). The data sets were analyzed visually by two independent readers, using standard left ventricular planes, concerning regional wall motion abnormalities. DSCT was verified in a blinded fashion against cine ventriculography performed during cardiac catheterization (RAO and LAO projection), using a 7-segment model. Analysis was performed on a per-patient (presence of at least one hypo-, a- or dyskinetic segment) and on a per-segment basis. RESULTS: Concerning the presence of a wall motion abnormality, the two observers agreed in 340/350 segments (97%) and 48/50 patients (96%). In invasive cine angiocardiography, 22 of 50 patients displayed at least one segment with abnormal contraction. To detect these patients, DSCT showed a sensitivity of 95% (21/22), specificity of 96% (27/28), positive predictive value of 95% and negative predictive value of 96%. Out of a total of 350 left ventricular segments, 66 segments had abnormal contraction in cine angiocardiography (34 hypokinetic, 26 akinetic, 6 dyskinetic). For detection of these segments, DSCT had a sensitivity of 88% (58/66), specificity of 98% (278/284), positive predictive value of 91% (58/64) and negative predictive value of 97% (278/286). CONCLUSION: DSCT allows the detection of regional wall motion abnormalities with high interobserver agreement as well as high sensitivity and specificity. Whereas sensitivity and positive predictive value were higher in a per-patient- in comparison to a per-segment-based analysis, specificity, negative predictive value and interobserver agreement did not differ considerably between both analyzing methods.


Assuntos
Angiocardiografia/métodos , Tomografia Computadorizada por Raios X/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Eur J Clin Invest ; 39(1): 31-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19067736

RESUMO

BACKGROUND: Growing evidence shows that inflammation plays a pivotal role in the pathophysiology of essential hypertension (EH). Vascular endothelial cell growth factor (VEGF) is currently discussed as a possible mediator of inflammation. To investigate the hypothesis that VEGF plays a role as an inflammatory mediator in EH we performed the present pilot study of young patients in a very early stage of EH. MATERIALS AND METHODS: 15 young patients with mild EH [33.8 +/- 7.3 years, systolic blood pressure (SBP): 143.8 +/- 10.5 mmHg, diastolic blood pressure (DBP): 88.2 +/- 11.1 mmHg, mean arterial pressure (MAP) 106.6 +/- 10.4 mmHg] and 15 healthy controls (31.7 +/- 10.6 years) were examined. Blood was drawn from a peripheral vein and serum levels of VEGF, monocyte-chemoattractant-protein (MCP)-1, high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, and tumour-necrosis-factor (TNF)-alpha were measured via commercially available enzyme-linked immunoassays. RESULTS: Hypertensives showed increased plasma levels of VEGF (P < 0.05) and MCP-1 (P < 0.05). VEGF positively correlated with MAP (r = 0.46, P < 0.05) and MCP-1 (r = 0.63, P < 0.01). Multivariate analysis demonstrated VEGF to be an independent predictor of MCP-1 levels. Furthermore, hypertensives had higher levels of hsCRP (P < 0.01), IL-6 (P < 0.001) and TNF-alpha (P < 0.05). IL-6 levels correlated with SBP (r = 0.59, P < 0.001), DBP (r = 0.67, P < 0.001) and MAP (r = 0.46, P < 0.001). A significant positive correlation was also found between hsCRP levels and SBP (r = 0.39, P < 0.05). CONCLUSIONS: This pilot study demonstrates that in an early state of EH, inflammatory pathways have already been activated. Besides classical pro-inflammatory cytokines, VEGF serum levels are significantly elevated. The positive correlation of VEGF with MCP-1 is suggestive for the already described induction of MCP-1 via VEGF.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/sangue , Mediadores da Inflamação/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Hipertensão/fisiopatologia , Mediadores da Inflamação/sangue , Masculino , Projetos Piloto , Fator A de Crescimento do Endotélio Vascular/sangue , Adulto Jovem
14.
Eur Radiol ; 18(12): 2770-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18604538

RESUMO

In coronary CT angiography (CTA), both high-grade stenoses and total occlusions of a coronary artery may appear as a complete interruption of the contrast-enhanced lumen. Parameters to differentiate between occlusions and stenoses have not been systematically assessed. We evaluated 40 consecutive patients with a lesion demonstrating complete interruption of the contrast-enhanced lumen in coronary CTA and in whom invasive coronary angiography was available. Length of the vessel segment without luminal contrast enhancement; luminal enhancement proximal, in and distal to the lesion; degree of coronary remodelling; and the degree of lesion calcification were assessed by a blinded observer unaware of the invasive angiogram. Mean length of complete occlusions (n = 20; range 4-54 mm; mean 16.6 +/- 3.5 mm) was significantly longer than for high-grade stenoses (n = 20; 2-8 mm; mean 4.6 +/- 1.7 mm, p < 0.001). A lesion length > or = 9 mm was 100% specific and 70% sensitive for an occlusion. No significant differences were found for vessel enhancement in or distal to the lesion, remodelling index or degree of calcification. Lesion length is the only parameter that may differentiate complete occlusions and high-grade stenoses in coronary CTA. For lesions > or = 9 mm, an occlusion is very likely.


Assuntos
Calcinose/diagnóstico por imagem , Angiografia Coronária/métodos , Oclusão Coronária/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Heart ; 94(1): 65-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17575327

RESUMO

BACKGROUND: Increasing scientific data suggest a role for inflammation in chronic heart failure (CHF), but up to now the exact mechanisms are still not clear. Recently, platelets were identified as inducing inflammation partly by releasing cytokines. This new aspect necessitates further studies about the contribution of platelets for the inflammatory setting of CHF. METHODS: 50 CHF patients (mean 66.9 (SD 12.6) years, mean EF 22.1% (SD 9.1)) and 25 healthy controls (mean 63.6 (SD 10.2) years) were examined. MCP-1 serum levels were measured via EIA, expression of platelet CD154 by flow cytometry. In in-vitro experiments activated platelets were cocultured with human umbilical vein endothelial cells (HUVEC) in the presence and absence of anti-CD154 antibodies. MCP-1 in the supernatants was measured by EIA. RESULTS: CHF patients showed significantly enhanced MCP-1 levels (median: 191.8; 25th centile: 153.7; 75th centile: 227.1 pg/ml vs median: 101.0; 25th centile: 86.7; 75th centile: 117.5 pg/ml, p<0.001). MCP-1 levels positively correlated with severity of CHF. In the cell coculture model activated platelets were able to significantly induce MCP-1 release from HUVEC in a CD154-dependent manner. Furthermore, CHF patients showed enhanced platelet CD154 expression with a positive correlation with MCP-1 levels. Aspirin therapy had no influence on either CD154 expression or MCP-1 levels. CONCLUSIONS: Platelets can contribute to enhanced MCP-1 levels in CHF. MCP-1 is markedly elevated in serum of CHF patients showing a direct correlation with the severity of symptoms and the degree of left ventricular dysfunction. Further studies are required to test whether MCP-1 blocking or sophisticated anti-platelet strategies may represent new therapeutic options in CHF.


Assuntos
Quimiocina CCL2/sangue , Insuficiência Cardíaca/sangue , Ativação Plaquetária , Idoso , Ligante de CD40/sangue , Cardiomiopatia Dilatada/sangue , Doença Crônica , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Masculino
16.
Rofo ; 179(9): 953-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17492542

RESUMO

PURPOSE: Multidetector CT (MDCT) is a reliable tool to assess and quantify calcified plaque in coronary arteries. Only very limited information is available concerning the accuracy of MDCT for evaluating non-calcified plaque. We determined the interobserver variability for measuring non-calcified plaque volumes in the three main coronary arteries using 64-slice computed tomography. MATERIALS AND METHODS: We retrospectively evaluated data sets of 41 patients who received a 64-slice CT scan (Sensation 64, Siemens Forchheim, Germany, 330 msec rotation, 0.6 mm collimation, 60 ml contrast agent i. v. at 5 ml/sec) due to suspected stable coronary artery disease. The patients showed presence of non-calcified plaque in the proximal part of at least one main coronary artery. The image quality was defined on the basis of a 4-point rating scale. Two independent and blinded investigators measured the plaque volume of the non-calcified plaque by manually tracing plaque areas in contiguous cross-sectional reconstructions rendered along the vessel centerline using a slice thickness of 1 mm and an increment of 0.5 mm. The interobserver variability was evaluated and the influence of plaque volume and image quality on interobserver variability was determined. RESULTS: The mean volume of non-calcified plaque was 157 +/- 85 mm (3), 76 +/- 43 mm (3) and 133 +/- 80 mm (3) for the LAD, LCX and RCA, respectively (LAD vs. LCX: p < 0.01; LAD vs. RCA: p = 0.33; LCX vs. RCA: p < 0.01). There was a mean absolute difference in plaque volume between the two observers of 23 +/- 15 mm (3), of 20 +/- 9 mm (3) and of 38 +/- 21 mm (3), which corresponds to a mean interobserver variability of 17 +/- 10 %, 29 +/- 13 % and 32 +/- 13 % for the LAD, LCX and RCA, respectively (LAD vs. LCX: p < 0.01; LAD vs. RCA: p < 0.01; LCX vs. RCA: p = 0.87). A significant inverse correlation between interobserver variability and the extent of the plaque volume (r = - 0.48; p = 0.01) was found. Interobserver variability was dependent on image quality: The highest image quality was observed in the LAD (2.4 +/- 0.5), while the image quality in the LCX (2.1 +/- 0.7) and the RCA (2.0 +/- 0.6) was lower. CONCLUSION: Interobserver variability for the quantification of non-calcified plaque volumes in 64-slice MDCT is substantial. Interobserver variability in the LAD was significantly lower than in the LCX and the RCA. This might be due to a larger mean plaque volume and better image quality in the LAD than in other coronary arteries.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos , Software , Estatísticas não Paramétricas
18.
Dtsch Med Wochenschr ; 132(14): 741-5, 2007 Apr 05.
Artigo em Alemão | MEDLINE | ID: mdl-17393345

RESUMO

HISTORY: A 42 year-old man reported transient breathlessness and chest pain on the first day after a four-hour flight. During the following five months the symptoms recurred four times. After another episode he went to an outpatient department for further assessment. INVESTIGATIONS: Blood tests demonstrated slightly elevated LDH (343 U/l) and also a minor increase of the D-dimers (710 microg/l). Hypercholesterolemia was also found (LDL-cholesterol 180 mg/dl). The rest of the blood tests, including the cardiac enzymes, were within normal limits. The electrocardiogram (ECG) showed sinus rhythm, heart rate 85 bpm and pre-terminal T-negativity in the precordial leads V1 to V3. Resting echocardiography and chest X-ray showed no significant abnormalities. The exercise ECG demonstrated no further ECG changes. However, because of the symptoms and a cardiovascular risk profile (family history, hypercholesterolemia and smoking) a coronary angiography was performed, which excluded coronary artery disease but revealed a so-called "right-sided single coronary artery", the left and right coronary arteries originating with a common stem from the right sinus of valsalva. To define the exact course of the left main coronary artery (whether in front of the pulmonary artery, between the two great arteries, retroaortic or septal) a contrast-enhanced cardiac computed tomography (CT) was performed, which demonstrated an anomalous position of the left main coronary artery in front of the pulmonary artery. Bilateral pulmonary embolism was an additional and unexpected finding. TREATMENT AND COURSE: Oral anticoagulation was initiated after a coagulopathy had been excluded. The ultrasonography of the leg did not demonstrate any thrombosis. There was no evidence of malignant disease. CONCLUSION: Mild symptoms and absence of right heart congestion do not exclude pulmonary embolism. Depending on the symptoms and history, pulmonary thrombembolism has to be considered, especially if cardiac or extra-cardiac causes have been eliminated. The diagnostic method of choice for the detection or exclusion of pulmonary embolism is contrast-enhanced multi-slice spiral CT.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Tomografia Computadorizada Espiral , Adulto , Dor no Peito , LDL-Colesterol/sangue , Angiografia Coronária , Anomalias dos Vasos Coronários/complicações , Dispneia , Eletrocardiografia , Humanos , L-Lactato Desidrogenase/sangue , Masculino , Embolia Pulmonar/complicações , Recidiva , Tomografia Computadorizada Espiral/métodos , Tomografia Computadorizada Espiral/normas
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